When sourcing Ipe (Brazilian Walnut), the price is heavily dictated by density and moisture content. You should prioritize kiln-dried (KD) lumber with a moisture content of 10-12% for interior use or Air-Dried (AD) at approximately 18% for exterior decking to prevent warping. Ensure the wood has a Janka Hardness rating of approximately 3,680 lbf, making it one of the most durable structures available. For '180' specifications (often referring to 180mm width or specific length increments), verify dimensional stability and a Class A fire rating, which is equivalent to concrete or steel.